Differentiation Modifications Have students develop the experimental design on their own using the tools provided. For example, students may choose to set up a control treatment as a chamber with BTB and no soda water. Tips Addressing problems at this point as students try to find patterns in data will support their learning in future investigations. This is the first investigation, so it is likely to expose challenges that may come up again. Extending the Learning Students may want to compare what happens with soda water fizzing with other conditions, such as seeing what happens to mass and BTB with plain water in the Petri dish, or how their observations are affected by the amount or temperature of the soda water.